ADHESIVE FOR DIFFICULT TO BOND SURFACES

摘要

Improved aqueous emulsion vinyl acetate-ethylene (VAE) polymer adhesives for use in packaging applications and on difficult to bond surfaces such as poly ethylene, poly(ethylene terephthalate) and oriented polypropylene. The VAE polymers co ntain about 55-80 wt% vinyl acetate 15-45 wt% ethylene and 0-30 wt% of one or more additional ethylenically unsaturated copolymerizable monomer, based on the t otal weight of monomers. Cast films of the VAE emulsion polymers of this invention shoul d have a tensile storage modulus (test frequency of 6.28 rad/sec) within the area enc ompassed by the following data points: 1x10 5 and 2x10 7 dynes/cm2 at 23 .degree.C, a nd 1x10 3 and 2X10 6 dynes/cm2 at 70 .degree.C; preferably within the area encompassed by the fol lowing data points: 1x10 6 and 1.5x10 7 dynes/cm2 at 23 .degree.C and 3x10 4 and 9x10 5 dynes/cm2 at 70 .degree.C.